Multiplex telegraphy.



N0 799,567. PATENTED SEPT. 12, 1905.

I G.L.HOGAN.

MULTIPLEX TELBGRAPHY.

APPLICATION FILED AUG. 11, 1902.

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No. 799,567. PATENTED SEPT. 12, 1905. G. L. HOGAN.

MULTIPLEX TELEGRAPHY.

APPLICATION FILED AUG. 11, 1902.

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MULTIPLEX TELBGRAPHY.

APPLICATION FILED AUG.11, 1902.

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No. 799,567. PATENTED SEPT. 12, 1905. G. L. HOGAN.

MULTIPLEX TELEGRA'PHY.

APPLICATION FILED AUG.11,1902.

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No. 799,567. PATENTED SEPT. 12, 1905. G. L. HOGAN. MULTIPLEX TBLEGRAPHY.

APPLICATION FILED AUG.11,1902.

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No. 799,567. PATENTED SEPT. 12, 1905. G.L.HOGAN.

MULTIPLEX TELEGRAPHY.

APPLICATION FILED AUG. 11, 1902.

10 SHEETS-SHEET 6.

No. 799,567. PATENTED SEPT. 12, 1905, G. L. HOGAN.- MULTIPLEXTELEGRAPHY.

APPLICATION FILED AUG.11,1902.

' 10 SHEETS-SHEET 7.

No. 799,567. PATENTED SEPT. 12, 1905.

e. L. HOGAN.

MULTIPLBX TBLEGRAPHY.

APPLIUATION FILED AUG. 11, 1902.

10 SHEETS-SHEET 8.

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MULTIPLEX TELEGRAPHY.

APPLICATION nLnn we. 11, 1902.

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- PATENTED SEPT. 12, 1905.

G. L. HOGAN. MULTIPLEX TELEGRAPHY. APPLIOATIOR mum man, 1902.

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m g .m% Mm MW A w m1 7 a. .0 J W m 2 w w i i lumuw a cnnuu cu,PNDTO-LITNOGRAPHHS. waswmcmu u c UNITED STATES PATENT OFFICE.

GEORGE LEWIS-HOGAN, OF LONDON, ENGLAND.

MULTIPLEX TELEGRAPHY.

To all whom it may concern:

Be it known that I, GEORGE LEwrs H OGAN, a citizen of the United Statesof America, residing at the Hotel Cecil, Strand, London, England, haveinvented a new and usefulImprovement in Multiplex Telegraphy,of whichthe following is a specification.

This invention relates to the transmission of telegraphic messages, andis especially directed toward improving multiplex systems in which agiven transmission or signaling line or medium is arranged between aplurality of sets of transmitting and receiving instruments at one endof the line and a plurality of corresponding sets at the other end ofthe line, each set at one end of the line being arranged, when connectedwith the corresponding set at the other end of the line, to form acomplete system for the transmission of electric impulses, means beingprovided for repeatedly intermittently connecting in rapid successionthe transmission-line with and disconnecting the same from a pluralityof the sets at one end of the line and a plurality of the sets at theother end, said means consisting of electromagnetic mechanism actuatedby a synchronizing fluctuating electric current or currents, whereby theconnections at the two ends of the line are efiected synchronously.

One feature of the present invention consists in placing thetransmission line or wire in consecutive or repeated electricalconnection with three contacts, instruments, or systems at one stationand three corresponding ones at another station by means of asynchronizing-current consisting of a series of alternately positive andnegative electric impulses separated by zero periods, the positiveimpulses effecting one contact, the zero period another contact, and thenegative impulses the third.

Another feature of this invention consists in the provision of means forrendering the receiving instruments at the sending-station inoperativeduring the interval of time dur ing which the sending-station isdisconnected from the transmission-line.

Another feature of this invention consists in employing thesynchronizing line or medium also as a signaling line or medium, thesignaling being effected by adding increments to the synchronizingelectric impulses.

Another feature of the present invention consists in the combination,with the multirepeating the various currents and impulses.

Specification of Letters Patent.

Patented Sept. 12, 1905.

Application filed August 11, 1902. Serial N0.l19,3171

For instance, when a signaling-circuit and a combined synchronizing andsignaling circuit are employed means may be provided for repeating thesignaling-currents of the signaling-circuit onto anothersignaling-circuit and for repeating the synchronizing-currents and itssignaling increments onto another combined sychronizing and signalingcircuit.

Other features and combinations are hereinafter pointed out as beingessentially part of the invention.

In order that this invention may be clearly understood, variousembodiments of the same are by way of example illustrated in theaccompanying drawings and hereinafter described with reference thereto.

In said drawings, Figure 1 illustrates diagrammatically an arrangementof the telegraphic apparatus and circuits in the application of thisinvention to three quadruplex systems of the bridge type. Fig. 2 is afront elevation of atwo-way distributer, hereinafter described. Fig. 3is a front elevation of a distributer adapted to efiiect the connectionscorresponding to the zero periods of the synchronizing-current. Fig.Lisa diagrammatic representation of a generator for producing alternatepositive and negative electric impulses separated by zero periods. Fig.5illustrates a distributer inclosed in an air-tight case containinggases under a pressure greater than normal atmospheric pressure. Fig. 6illustrates diagrammatically an arrangement of the telegraphic apparatusand circuits at one end of a transmission-line in the application ofthis invention to three quadruplex systems of the differential type.Fig. 7 illustrates a system by which six differential quadruplexstations which are widely separated can simultaneously communicate witheach other in pairs by means of one transmission-line. Fig. 8illustrates one end of a system in which the synchronizingline of atriple differential quadruplex system is also utilized as asignaling-line. Fig. 9 indicates graphically the nature of thesynchronizing-current generated by the generator shown in Fig. 4. Fig.10 indicates graphically the nature of the cur' rent in thesynchronizing-circuit when increments are added to the ordinarysynchronizingimpulses for signaling purposes. Fig. 11 diagrammaticallyillustrates means for repeating the signaling-currents passing along oneway of a three-Way or triple quadruplex system and also means forreperting the synchronizing impulses and the signaling increments ICC olthe synchronizing impulses. Fig. 12 is a front elevation of a three-waydistributer having a polarized armature and a non-polarized armature.Fig. 13 is a part-sectional side elevation of the same. Fig. lt is aplan of the same. Fig. 15 illustrates diagrammatically the method ofconnecting up said three-way distributer. Fig. 16 diagrammatically showsmeans for generating the synchronizing impulses from two direct-currentgenerators and means for repeating the synchronizing impulses.

iet'erring to Fig. 1,the instruments and connections 1 are adapted toform, when connected with the instruments and connections 2, a singlequadruplex telegraph system of the bridge type, and similarly quadruplexsets 3 and 1, when connected together, are adapted to form a quadruplexsystem, and similarly the sets 5 and 6 are adapted, whenintercnnected,to form a quadruplex system. These six quadruplex sets ofthe bridge type may be arranged as shown or in any other suitablemanner. In each of these sets 7 is the battery, 8 the reversing-key, 9the increment-key, 10 a polarized sounder, 11 a non-polarized sounder,12 the artificial line, and 13 14 balancing resistances. The instruments10 and 11 may be considered as polarized and non-polarized relays foroperating their respective sounders, the arrangement usually used inordinary practice. The batteries 7 are split up in the well-known mannerinto parts 7 7" 7 7 all in series on the line 7, which is earthed at 7and is connected at its other end in parallel to the balancingresistances 13 14. The parts 7 and 7" are respectively single-cell andthree-cell batteries adapted to send negative current through the line,while the parts 7 and 7 are two-cell and six-cell batteries adapted tosend positive current through the line. Between 7 and 7 is connected awire 7, leading to'terminal 9 of the incrementkey. Between 7 and 7 areconnected two wires, one, 7 leading to the reversing-key 8 and theother, 7", leading to the increment-key 9. Between 7 and 7 is connecteda wire 7 leading to the key 9, and between 7 and earth are connected twowires 7" and 7", leading, respectively, to terminals 8 of thereversing-key 8 and 9" 01 the increment-key 9. The artilicial line 12lies in a wire 12, connected at one end to thewire 14?, between thebalancing resistance 14 and the non-polarized sounder 11 and 'earthed atthe other end. The balancing resistance 13 is connected to the polarizedsounder by wire 13" and is also connected in parallel by a wire 13 tothe contact-terminal 25, as and for the objects more fully describedbelow. The manner of working a quad rupleX set of this character is verywell known to telegraph-engineers. The arrangement was, it is believed,first described in British Patent of Thomas A. Edison, No. 384: of 1875.It is therefore needless to further describe it here. The arrangement isalso described with some differences in United States Patent No. 209,241of 1878, T. A. Edison. The distributers or circuit-closers 16 17 18 1927 28 29 30 are adapted to connect the transmission line 15 repeatedlyand consecutively between a nd to disconnect the same from the sets 1 2,3 4:, 5 6 in rapid succession and to render the receiving instruments 1O11 inoperative during the interval of time during which said receivinginstruments are disconnected from the transmission or signalling line 1515, and the frequency of the change of connections effected by thedistributers is so high that the change of connections is notdetrimental to the reading of signals.

Each of the distributers 16 17 18 19, as shown in Fig. 2, comprises anelectromagnet 20, provided with an oscillatory polarized armature 21,pivoted on the pivot 22 and provided with a projection 23, to which thead justing-spring 2 1 is connected. The armature, according to thedirection of the current flowing through the coils of the electromagnet,makes contact with one or other of the stops 25 26. The spring 24:maintains the armature out of contact with both stops while no currentis flowing.

Each of the distributers 27 28 29 30, as shown in Fig. 3, comprises anelectromagnct 31, provided with a non-polarized armature 32, pivoted onthe pivot 33 and having a tailpiece 3t, to which the adjusting-spring isconnected. When either a positive or anegative current flows round thecoils of the electromagnet, the armature is attracted to theelectromagnet and the contact between the armature and the contact-stop36 is broken. During the period in which no current flows through thecoils of the electromagnet the armature on account of the tension of thespring makes contact with the stop 36.

Referring once more to Fig. 1, it will be seen that all themagnetizing-coils of the distributers are arranged in series in thecircuit 37 37, which is grounded at its two ends at 38 38. Said circuit,which is called the synchronizingcireuit, contains the generator 39,which may conveniently be a magnctogenerator. I prefer to employ amagnetogenerator of the construction diagrammatically represented byFig. 4:, in which 40 represents the permanent field-magnet, 41 thearmature-core. 12 42 the armaturecoils, 4:3 43 two collector-rings, 44141 connections between the armature-coils and said col lector-rings, 1545 the two brushes. It will be observed that the width of thearmaturecore between the armature-coils is so great relatively to thebreadth of the pole-pieces 46 46 that when the armature is in theposition indicated in Fig. 4 a large proportion of the lines of forcepass through all the winding of the armature-coils and that this reconnected with the quadruplex set 2.

distributers 29 30.

mains the case while the armature turns through a considerable angleabout the position shown in Fig. 4-that is to say, while the armatureturns through a considerable angle in the neighborhood of the positionshown in Fig. 4 the number of lines embraced by the armature-windingremains practically at a maximum, and consequently the zero period .ofthe current generated by the armaturecoils is considerable and inpractice is conveniently made approximately equal to the periods inwhich the negative and positive currents are being generated.

Fig. 9 indicates graphically the nature of the synchroniZing-currentgenerated by a generator such as that shown in Fig. 4. In Fig. 10lengths along the axis represent time and ordinates at right angles tothe axis represent current strength. The period between 48 and 49represents a period of positive current. The period between 49 and 50represents a period during which the current generated is almost zero,hereinafter called the Zero period, and the period between 50 and 51 theperiod of negative current. 52 52 may consequently represent a series ofpositive current impulses and 53 53 a series of negative currentimpulses.

Referring to Fig. 1, it will be seen that the armatures of thedistributers 16 17 of the quadruplex sets 1 2, respectively, aredirectly connected with the two ends of the transmission-line 15, thestop of the distributer 16 being connected with the quadruplex set 1 andthe stop 25 of the distributer 17 being The quadruplex sets 3 4 arerespectively connected with the contact-stops 36 36 of the distributers27 28, while the quadruplex sets 5 6 are respectively connected with thecontact-stops 26 26 of the distributers 16 17. The bridgewires 54 54 ofthe quadruplex sets 1 2 are broken and the two sides of the break areconnected with the contact-stops 25 25 of the distributers 18 19 andwith insulated contactpieces 55 55, mounted upon the armatures of saiddistributers. The bridge-wires 56 56 of the sets 3 4 are similarlybroken and the free -ends of the break connected with the contactstops36 36 and the armatures 32 32 of the The bridge-wires 57 57 of the sets5 6 are similarly broken and the free ends connected with thecontact-stops 26 26 and the armatures of the distributers 18 19. Themanner in which this triple quadruplex system (illustrated in Fig. 1)can be operated in such a manner that the twelve operators of the twelvekeys can operate simultaneously with the corresponding operation of thecorresponding receiving instruments will be understood from thefollowing explanation: The positions of the various armatures of thedistributers (shown in Fig. 1) may be supposed to be produced by apositive impulse flowing through the synchronizing-circuit 37 37. Itwill be noticed that both of the armatures of the distributers 16 17 aremaking contact with the contact-stops 26 26 and are consequently placingthe quadruplex sets 5 6 in direct communication with each other throughthe transmission-line 15 15. It will also be observed that the armaturesof the distributers 18 19 are also making contact with theircorresponding contact-stops 26 26 and are consequently completing thebridgewires 57 57 of the two sets. Consequently during the passage of apositive impulse the sets 5 6 form a complete quadruplex system whichcan be operated in the ordinary manner. During the passage of a positiveimpulse it will be observed that the sets 1, 2, 3, and 4 are entirelydisconnected from the transmission-line. On the positive current ceasingto flow and during the Zero period the armatures of the distributers 1617 18 19 will be in neutral positions similar to the position shown inFig. 2 and will effect no contact, whereas the armatures of thedistributers 27 28 29 30 will make contact with their respectivecontact-stops 36 36 and the distributers 27 28 will place the sets 3 4in direct communication with each other through the transmission-line 15and the armatures 32 32, while the distributers 29 30 willsimultaneously close the bridge-circuits 56 56 by means of theirarmatures 32 32 and stops 36 36. Consequently the sets 3 4 will now bealone in communication with the line and will form a quadruplex systemadapted to be operated in the ordinary manner. During the passage of anegative impulse it will readily be seen that the sets 1 2 will beplaced in direct communi cation with the line 15 through the stops 25and the armatures ot' the distributers 16 17, while the sets 3 4 5 6will be entirely disconnected therefrom, and that during the connectionof said sets 1 2 with the line their bridgewires 54 54 will be completedby the insulated contact-pieces 55 on the armatu res of the distributers18 19 making contact with the stops 25 25 of said distributers.Consequently the sets 1 2 can be operated in the o dinary manner as acomplete quadruplex system. The reason on account of which thebridge-wires of the various quadruplex sets are opened or interruptedduring the intervals of time during which the corresponding sets aredisconnected from the transmission-line is that if the bridge wires werenot so interrupted the home receiving instruments would be operated onthe depression of the home keys on the disconnection of the quadruplexset from the transmission-line, as the balance existing duringconnection with the transmission-line is destroyed as soon asdisconnection occurs. It is to be understood, however, that instead ofbreaking the bridge-wires the system will operate satisfactorily if thebattery-circuits are interrupted in a similar manner. Instead of,however, interrupting the bridge-wires or the battery-circuits extraresistance in these circuits might be introduced to achieve the sameresult, or the receiving instruments may be short-circuited.

In the transmission of telegraphic impulses, such as dots and dashes, inthe manner described, it is of course understood that the dots anddashes are broken into parts and transmitted in sections, the partsforming one telegraphic impulse being transmitted alternately with partsforming other telegraphic impulses of one of the other quadruplexsystems.

It is of course understood that the distributers at the two ends of theline are operated synchronously by the synchronizing-current generatedby the magneto-generator or other equivalent source.

In order to improve the synchronizing of the various distributers, thegenerator of the synchronizing-current may be connected midway betweenthe two stations at the two ends of the line in order that the effect ofleakage on the current operating the distributers may be equalized.

It is of course necessary to oscillate the armatures of the distributersat such a rate that the reading of the messages is not interfered withby the intermittent manner in which the quadruplex sets forming onecomplete system are connected with each other through the line.

In order to minimize sparking occurring at the contacts of thedistributers, the distributers may be inclosed in an air-tight case 58containing gases under a pressure greater than that of normalatmospheric pressure. Fig. 5 shows two distributers 59 60 mounted uponframe 61, inclosed in said air-tight case. case 58, which mayconveniently be of glass, is shown mounted upon the base-plate 62,through which the supply-pipe 63 is adapted to lead the gases underpressure.

Fig. 6 shows diagrammatically the apparatus at one end of a lineoperated, according to the present invention, on a triple differentialquadruplex system, the two ends of the line being practically identical.The manner of operation of the whole system will be readily understoodby reference to this figure, showing the apparatus at one end of theline. In this figure, 64 65 66 are three differential quadruplex sets,each of which when connected through the line with one of threecorresponding sets at the other end of the line is adapted to beoperated as a differential quadruplex system in the ordinary manner. Thedistributers are arranged with reference to these three sets in asimilar manner to the way in which the distributers 16, 27, 29, and 18are arranged with reference to the quad ruplex sets 1 3 5, as shown inFig. 1 and in Fig. 6. The same parts in connection with the distributersare designated by the same reference-numerals as those which designatesimi- The lar parts in Fig. 1. The same apparatus is conveniently usedin the sets 64 65 66. 67 in each set is the increment-key of a localcircuit 68, adapted to operate, by means of an electromagnet 69, theincrement-transmitter 70. 71 is the reversing-key, arranged in the localcircuit 72 and adapted on being depressed to operate, by means of theelectromagnet 73, the reversing-transmitter 74:, which may be of anyconvenient type. 75 is the battery; 76, a receiving instrument of theordinary type, having a polarized armature 77 and anon-polarizedarmature 78. The polarized armature 77 is adapted when operated to closethe local circuit in which the sounder 7 9 is arranged. Thenon-polarized armature 78 when operated is adapted to open the localcircuit containing the electromagnet 80, which when demagnetized dropsits coacting armature and closes the local circuit containing thesounder 81. 82 is the artificial line. 83 is an adjustable resistance,and 84 is an adjustable condenser for obtaining balance. 85 86 arechoking or inductance coils for balancing the self-induction of the lineand instrul'nents con nected therewith. It is to be understood that eachof the differential quadruplexsets 64 65 66 and the corresponding setsat the other end of the line may be of any ordinary or suitable type.The manner in which the system accordingto Fig. 6 is operated is similarto the manner of operation of the system shown in Fig. 1. The three setsat one end of the line are successively connected one at a time to thetransmission-line, synchronous connections of the corresponding sets atthe other end of the line being effected by means of the distributersabove described, and during the interval of time during which any oneset is disconnected from the line the circuit of the artificial line isalso broken in order that the home receiving instruments may not beoperated by the home transmitters during the disconnection of the setfrom the transmissionline. It is to be understood, however, that insteadof breaking the artificial line the battery-circuit may be broken, or,on the other hand, the receiving instrument or instruments may beshort-circuited during the disconnection of the set from the line. Infact, any convenient means may be employed for rendering the receivinginstruments inoperative during the time of disconnection of the set fromthe line.

It is of course to be understood that the present invention may beapplied to a system in which three duplex systems of either the bridgeor the differential type are arranged at the two ends of thesignal-transmission line. The method of operation of such a tripleduplex system is in principle similar to the method of operation of thetriple quadruplex systems above described, the actual connections,however, being considerably simpler.

Fig. 7 illustrates a system by which the six differential quadruplexsets 87 88 89 90 91 92, which are placed at wid ely-separated stations,can simultaneously communicate with each other in pairs by means of thesignal-transtributers 96 97 98 99 100.

mission line 93 93. The set 87 commiu'iicates with 92, 88 with 91, 89with 90. 94 9 1 represent the synchronizing-circuit, containing the dis-101 101 are the siX quadruplex receiving instruments, each having apolarized and a non-polarized armature,and 102 102 is the artificialline of each set. Each of the armatures of the distributers 95 96 97 9899 100 carries an insulated contactpiece, 95 96 97 98 99 100.respectively, at one end, which is adapted when in contact with itscorresponding stationary contact to short-circuit one side of thereceiving instrument 101. Each of the armatures of the distributers 9596 99 100 is permanently connected with the transmissiouline 93, and thearmature is adapted to make contact with a contact-stop which isconnected with the receiving instrument. Each of the armatures of thedistributers 97 98 is connected permanently with the correspondingreceiving instrument 101 and is adapted when operated to make contactwith a contact-stop permanently in connection with thetransmissioi'iline 93. The method of operation is as follows: Supposinga positive current impulse to flow along the synchronizing-line, thearmatures oi the various distributers will be in the positions indicatedin Fig. 7, the set 87 being connected through the armaturcs of thedistributers 95 and 100, the line 93 between the latter with the set 92and forming a complete differential quad ruplex system therewith, thesets 88 89 90 91 being disconnected from the transmission-line duringthe passage of the positive current impulse and one side of thereceiving instruments 101 of said four sets being short-circuited in themanner hereinbei'ore described. During the period of zero current in thesynchronizing-line the sets 89 and 90 will be directly connectedtogether through the transmission-line 93 and the armatures of thedistributers 97 98, the sets 87 88 91 92 being disconnected therefromand one side of their receiving instruments being short circuited.During the passage of the negative current impulse the set 88 will beconnected, through the line 93 and the armatures of the distributers 96and 99, with the set 91, the remaining sets being disconnected from theline and one side of their receiving instruments being short-circuited.In Fig. 7 the complete set of instruments for each quad ruplex set isnot shown, as any suitable quadruplex system may be employed, such asthose shown in Fig. 6.

Fig. 8 illustrates one end of a system in which the synchronizing-lineof a triple differential quadruplex system such as that illustrated byFig. 6 is also utilized as a signaling-line by adding increments ofcurrent to the synchronizing-current impulses of thesynchronizing-circuit. The upper portion of the diagram shown in Fig. 8illustrates one end of atriple quadruplex differential system such asthat illustrated in Fig. 6, only so much of the system being shown as issuflicient to make the connections of the whole system readilycomprehensible. Instead of grounding the synchronizing-line at 38, as inFig. 6, the synchronizing-line 163, Fig. 8, is connected in series witha two-way polarized distributer 10% and with the diiferential instrument105. The central portion of the differentially-wound receivinginstrument 105 is connected with the pivoted armature of the distributer10 1, which is adapted, according to the direction of current in thedistributer, to make contact with one or other of the contacts 107 108,connected through the direct-current generators 109 110, respectively,to earth through the keys 111 112, which are normally open. Thedifferential receiving instrument is provided with two polarizedarmatures 113 11 1, which when operated close the local circuits of thesounders 115 116. It is to be understood that the synchronizing-line 103is connected at each end to a set of instruments similar to that shownat the end of the synchronizingline shown in Fig. 8. If it is desired tosend a telegraphic message through the synchronizing-circuit from theend of the synchronizing-line shown in Fig. 8, either the key 111 or thekey 112 may be employed for the transmission of the signal impulses.Supposing the key 112 be employed, it is evident that when the armatureof the distributer is in contact with the contact block 108, as shown inFig. 8, an increment of current will pass from the direct-currentgenerator 110 through the block 108 and the armature of the distributer104 to the line at the instrument 105, and said increment-current willnot affect the differentially-wound home instrument 105, but will affectthe corresponding receiving instrument at the other end, as is wellunderstood in difierential duplex telegraph y. It should be mentionedthat the receiving instruments 105 at each end of the line are so setthat their armatures cannot be operated by the normalsynchronizing-current. A message can be equally well sent by employingthe key 111 instead of the key 112, in which case the signal is sent byadding increments to the negative current impulses in thesynchronizing-line, said increments being generated by the generator 109during the contact of the armature of the distributer 101 with thecontactblock 107, and passing through said block to the line at theinstrument 105. If two messages are to be simultaneously sent from theend of the line shown in Fig. 8, the keys 111 112 are operatedsimultaneously, in which case the positive-current increments operateone of the armatures of the distant receiving instrument and thenegative-current increments operate the other armature of the distantreceiving instrument, the home receiving instrumentbeing unaffected byeither set of impulses. Simultaneously with the transmission of one ortwo messages from the end of the line shown in Fig. 8 to the other endmessages may be sent from the distant end to the receiving instrument105, (shown in Fig.

8,) the armature 113 answering to, say, the positive-current incrementsand the armature 11 1 to the negative-curre nt increments. The nature ofthe impulses of the synchronizingcircuit during the increment of boththe positive and the negativesynchronizing impulses is illustratedgraphically by Fig. 10, the ordinates of the full lines indicating thestrength of the current in the synchronizing-circuit during the passageof these messages, and the ordinates of the dotted lines show the normalsynchronizing-current impulses, the difference between the ordinates ofthe dotted and full lines giving the strength of the currentincrementsemployed in signaling along the synchroniZing-circuit.

Fig. 11 illustrates means for repeating the synchronizing-currentimpulses from the circuit 117 117 onto the synchronizing-circuit 118118.There is no need to provide means for repeating backward from thecircuit 118 to the circuit 117. Fig. 11 also shows means whereby thesignaling-increments of the synchronizing impulses in the circuit 117can be repeated onto the circuit 118, and also means whereby suchincrements can be repeated from the circuit 118 onto the circuit117. Thelower portion of the diagram in Fig. 11 illustrates means for repeatingthe signaling-currents in the transmission-line 119 onto thetransmission-line 320, and also means for repeating thesignaling-currents from the transmissionline 320 in the oppositedirection onto the transmission-line'119. In order to repeat thesynchronizing-current impulses from the synchronizing-circuit 117 ontothe synchronizing-circuit 118, the synchronizing-line after beingconnected with the distributers which are provided for the repeating ofthe signaling-currents is connected in series with the two-way polarizeddistributers 120 121 and with the differentially-wound relay 122 andthrough the artificial line 123 and means for adjusting the same toearth 124:; The differential instrument 122 is set too high for thesynchronizing-current impulses to affect it. The oscillatorytl'l'l'litllUFG of the distributer 120 is connected with theconnecting-wire 125 and is adapted to make contact with the twocontactstops in connection with the d irect-currentgenerators 126 127,respectively, said generators being both connected with thesynchronizingline 118. The connecting-wire 125 is connected in serieswith the distributer 128 and with the dilferentially-wound relay 129 andthe artificial line and means for adjusting the same, 130, earthed at131. hen a positive synchronizing impulse flows through the circuit 117,the armature of the distributer 120 makes contact with the contact stopconnected with the current-gencrator 127, which thereby is connected inthe Synchronizing-circuit 118 and sends a positive synchronizing impulsealong said circuit, the strength of said impulse being insufficient toaffect the ditferential instrument 129. Similarly when a negativeimpulse passes along the synchronizing-circuit 117 the generator 126 isdirectly connected in the synchronizing-circuit 118, and said generatoris so connected that a negative current impulse passes along saidcircuit 118. During a Zero period in the circuit 117 the armature of thedistributer 120 does not connect either of the generators 126 127 in thecircuit 118, and consequently for every zero period in the circuit 117there is a corresponding zero period in the circuit 118, and, as abovedescribed, positive and negative impulses in the circuit 117 produce, bymeans of the generators 127 126, corresponding positive and negativeimpulses in the circuit 118. Referring now to the repeating of thesignaling-increments of the synchronizing impulses in the circuit 117onto the circuit 118, the differential instrument 122 is provided withtwo polarized armatures 132 133, arranged when operated to complete theelectromagnets 13 1 135 in corresponding local circuits. Theelectromagnet 131 is adapted to control the local circuit 136, in whichthe electromagnet 137 is arranged. This electromagnet 137 when energizedby means of its armature connects the generator 138 with thecontact-stop 139 of the distributer 128. The armature of theelectromagnet 135 is arranged to control the local circuit 140,containing the electromagnet 1 11, the armature of which when attractedis adapted to connect the direct-current generator 142 with thecontact-stop 140 of the distributer 128. The armature of the distributer128 is connected with the central point of the winding of thedifferential instrument 129. \Vhen a positive-increment signal passes inthe synchronizing-circuit 117, the differential instrument 1% isaffected, and the armature 133 is attracted to the electromagnet oftheinstrument, and the electron'iagnet 135 is energized, whereupon thelocal circuit 140 is closed, the electromagnet 1&1 is energized, and thegenerator 142 is connected with the stop 1 10. During the passage ofthis positive increment the armature of the distributor 126 willcomplete the circuit of the synchronizing-line 118 through the generator127, and the distributer 128 will, on account of the positive impulsegenerated by the generator 127, connect the central point of thedil'ferential instrument 129 with the stop 140, and consequently thegenerator 142 will add a positive increment to the current impulseprovided by the generator 127-that is to say, the postive-incrementsignal in the circuit 117 will be repeated onto the circuit 118. WVhenthe negative signaling-increment passes in the circuit 117, the armatureof the distributer 120 will make contact with the contact-stop connectedwith the generator 126 and the armature of the distributer 128 will makecontact with the contact-stop 139. The armature 132 of the differentialinstrument 122 will complete its local circuit, causing theelectromagnet 134 to close the local circuit 136 and energize theelectromagnet 137, which will connect the generator 138 with the stop139. Consequently to the negative impulse generated by the generator 126there will be added a negative increment generated by the generator138'. For each zero period in the circuit 117 there will be acorresponding zero period in the circuit 118, and consequently the meansdescribed are evidently adapted to repeat the positive increments, zeroperiod and negative increments following each other consecutively in thecircuit 117 onto the circuit 118.

In order to repeat positive and negative signaling-increments from thesynchronizing-circuit 118 onto the synchronizing-circuit 117, apparatussimilar to that just described is arranged. Referring to Fig. 11, itwill be seen that the armatures 143 144 correspond with the armatures133 132, respectively, the electromagnets 145 146 with theelectromagnets 134, respectively, local circuits 147 148 with the localcircuits 136, respectively, electromagnets 150 149 with theelectromagnets 141 137, respectively, the generators 152 151 with thegenerators 142 138, respectively, and the contact-stops 154 153 with thecontact-stops 140 139, respectively. The manner in which thesignaling-increments are repeated from the circuit 118 onto the circuit117 is similar to the manner in which they are repeated from the circuit117 onto the circuit 118 and will be readily understood from thedescription relating to the latter case.

Referring now to the repeating of the signaling-currents from thetransmission-line 119 onto the transmission-line 320, the lower portionof Fig. 11 shows means for repeating the signaling-currents of one ofthe quadrupleX sets of the complete triple quadruplex system, theapparatus required for the repetition of the signals of the remainingtwo quadruplex sets of signals being a repetition of the apparatusshown. The relation of the distributers 155 156 157 158 159 160 161 162to the means for repeating the signals of the three quadruplex sets willbe readily understood from the connections shown in Fig. 4. Thedistributers 155 156 157 158 are inserted in series in thesynchronizing-circuit 117, the distributers 159 160 161 162 beingconnected in series in the synchronizingcircuit 118. The repeating meansshown in Fig. 11 may impulses in the synchronizing-circuit 117.

Considering lirst the repetition of the signaling-currents from thetransmission-line 119 onto the transm1ss1on-hne 220, during the passageof the positive synchronizing impulses the armature of the distributor155 will make contact with the stop163, while the armature of thedistributer 158 will make contact with the stop 164. The armature of thedistributer 155 is thus during the passage of a positive impulseconnected through the stop 163 with the quadruplex instrument 165,provided with the polarized armature 166 and the non-polarized armature167, while the circuit 168 of the artificial line and means forbalancing the same, 169, will be completed by the armature of thedistributer 158 contacting with the stop 164. If the non-polarizedarmature 167 be attracted by the signalingcurrent, the electromagnet 170will close the local circuit of the electromagnet 171, which willoperate the increment-transmitter 172, which will send an increment ofcurrent along the transmission-line 320, the armature of the distributer159 making contact with the contact-stop 173 and the armature of thedistributer 163 making contact with the contact-stop 181, this incrementof current sent along the transmission-line 320 being a repetition ofthe increment of current received by the receiving instrument 165 andcausing operation of the non-polarized armature 167. If the polarizedarmature of the receiving instrument 165 be operated by thesignaling-current which passes through said receiving instrument, thelocal circuit of the electromagnet 174 will be completed, whereupon saidelectromagnet will close the local circuit in which the electromagnet175 is connected and said electromagnet on being energized will operatethe reversing-transmitter 17 6 and will reverse the current sent by thebattery 177 through the line 320. In this manner the signalingcurrentsreceived by the instrument 165 will be repeated by the transmitters 172176 onto the transmission-line 320. The manner in which thesignaling-currents are repeated from the transmission-line 320 onto thetransmission-line 119 is similar to the method of operation justdescribed, the receiving instrument 178 corresponding with the receivinginstrument 165, the armatures 179 180 with the armatures 166 167, thecircuit 182 with the circuit 168, the artificial line and means foradjusting the same, 183, with 169, the electromagnets 184 185 with theelectromagnet-s 170 171, the incrementtransmitter 186 with theincrement-transmitter 172, the electromagnets 187 188 with theelectromagnets 174 175, the reversing-transmitter 189 with thereversirig-transmitter 176, and the battery 190 with the battery 177.

In Fig. 11, 191 191 are sounders, which can be employed to receive themessages at the repeating-station, and 192 192 are keys or switcheswhich are closed when it is mcrely desired to receive the messages atthe repeating-station and not to repeat them.

Instead of employing two separate distributers, such as 1.55 156 or 157and 158, as indicated in Fig. 11, one distributer of each pair having apolarized oscillatory armature and the other a non-polarized armature, Iprefer to combine the two distributers in a single three-way distributerhaving a polarized armature and a non-polarized armature, as shown inFigs. 12 to 14, the electrical connections of said three-way distributerbeing indicated diagrammatically by Fig. 15. Referring to these figures,193 is the synchronizing-line which energizes the electromagnet 194. 195is a polarized oscillatory armature adapted to make contact with theadjustable contact-stops 196 197. 198 is a non-polarized armaturepivoted at 199 and adapted when no current flows from the electromagnetto rise against and make contact with the contact-stop 200. Thepolarized armature 195, which is pivoted on the pivot 201, is mounted onthe base 202, having a projection 203 engaging with a recess 204 in thepiece 205, mounted on the base of the distributer. An adjusting-screw206 engages with the base 202, and by turning the milled head 207 theposition of the base 205 can be adjusted, the polarized armature therebybeing brought nearer to or placed farther from the polepieces 208 209 ofthe electromagnet, whereby the strength of the field in which thearmature works can be adjusted. The contacts 196, 197, and 200 can alsobe individually adjusted and locked in position by thelock-nuts 210. Thenon-polarized armature can be adjusted by adjusting the tension-spring211, attached to the tailpiece 212 of the armature. The armatures ofthis three-way distributer are thus adapted to form three separate anddistinct contacts in a consecutive manner when an alternate currentactuates the distributer.

Fig; 16 shows means for generating the synchronizing impulses from twodirect-current generators and means for repeating the synchronizingimpulses. 245 is a magnetogenerator of any suitable form and is adaptedto rock the polarized armature of the electromagnet 246. Said. armature,which is connected with the line 247 247, is adapted to make contactwith contact-stops connected with the two direct-current generators 248249, one of which is adapted to send a positive impulse along the lineand the other a negative impulse. The distributer 250 is inserted at oneend of the line 247 and another distributer 251 at the other end of saidline, the line 247 being earthed at 252. The distributer 251 is providedwith an oscillatory armature, which is adapted to make contact with twocontacts connected with the two generators 253 254, and said armature isconnected with the wire 255, connected with the distributer 256. On thearmature of the distributer 251 being oscillated alternate positive andnegative impulses are generated by the generators 253 254, and saidimpulses pass through the armature to the line 255 and operate thedistributer 256, which is provided with an oscillatory armature. Thearmatu res of the distributers 250 256 are connected together by meansof the line 257, and as the distributors 250 256 are operatedsynchronously said line 257 is connected alternately through saidarmatures and their stops between the leads 258 259 and between theleads 260 261.

IVhat I claim is- 1. In a multiplex telegraphic system, the combinationof a plurality of sets of telegraphic instruments, each set such as tobe capable of communicating through one conductor with a similar set ofinstruments, means for supplying continuous electric current to saidsets of instruments, conveying means for the signals of saidinstruments, a rocking armature between each of the sets of instrumentsaforesaid and said conveying means adapted to electrically connect anddisconnect the set to and from the conveying means, a separate source ofelectric current, and a plurality of electromagnets controlled by thecurrent from said source adapted to operate in pairs atrapidly-succeeding intervals of time the connecting and disconnectingarmatures aforesaid between the sets of instruments and thesignal-conveying means.

2. In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments conveying means for the signals of said instruments, asource of electric energy giving a current composed of rapidly-succeeding impulses, separate conducting means for conveying saidcurrent, and means under-the control of said current consisting of anelectromagnet with rocking armature in connection with each set ofinstruments, adapted to connect and disconnect said sets of instrumentsin pairs in rapid succession to and from the signal conveying means.

3. In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, conveying means for the signals of said instruments, arocking armature between each of the sets of instruments aforesaid andthe conveying means adapted to electrically connect and disconnect thesets to and from the conveying means and to simultaneously renderoperative and inoperative respectively the receiving instruments of saidsets, a separate source of electric current, and a plurality ofelectromagnets controlled by said current adapted to operate in pairs atrapidly-succeeding intervals of time the connecting and disconnectingarmatures aforesaid between the sets of instruments and thesignal-conveying means. i

4. In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, conveying means for the signals of said instruments, asource of electric energy giving a current composed of rapidlysucceeding impulses, separate conducting means for conveying saidcurrent, and means under the control of said current consisting of anelectromagnet with rocking armature in connection with each set ofinstruments adapted to connect and'disconnect said sets of instrumentsin pairs in rapid succession to and from the signal-conveying means andto simultaneously render operative and inoperative respectively thereceiving in struments of said pairs of sets.

5. In a multiplex telegraphic system, the combination of six sets oftelegraphic instruments each set such as to be capable of communicatingthrough one conductor with a similar set of instruments, means forsupplying continuous electric current to said sets of instruments,conveying means for the signals of said instruments, a source ofelectrical energy adapted to give an alternating current in which eachalternation is separated from the next by an interval of approximatelyzero current, conducting means for conveying the current from saidsource, and six contact making and breaking devices under the control ofthe alternating current from said source, two of which devices areadapted to connect two of the sets of instruments to thesignal-conveying means during the period of positive impulse only, twoothers to connect two other sets of instruments to the signal-conveyingmeans during the period of negative impulse only, while the remainingtwo are adapted to connect the remaining two sets of instruments to thesignal-conveying means only during the period of zero current in thealternating circuit.

adapted to give an alternating current in which each alternation isseparated from the next by an interval of approximately zerocurrent,conducting means for conveying the current from said source, andsix contact making and breaking devices under the control of thealternating current from said source, said devices being adapted tooperate in pairs to connect each one i set of instruments to the signalconveying means during the periods of positive, zero and negativecurrent impulses respectively, and to render inoperative the receivinginstruments of the sets during the periods in which they aredisconnected from said signal-conveying means.

7. In a multiplex telegraphic system, the combination with a pluralityof sets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, conveying means for the signals of said instruments, asource of alternating electric current, conducting means for conveyingsaid current, and means under the control of said alternating currentadapted to connect and disconnect said sets of instruments in pairs inrapid succession to and from the signal-conveying means first mentioned,of a set of telegraphic instruments at each end of the conducting meanswhich carries the alternating current, the receivers of which sets ofinstruments are set too high to be affected by said alternating current,and means in connection with said sets of instruments last mentioned foradding increments to the alternations of the alternating current,substantially as and for the purpose set forth.

8. In a multiplex telegraphic system, the combination with a pluralityof sets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, conveying means for the signals of said instruments, asource of alternating electric current, conducting means for conveyingsaid current and means under the control of said alternating currentadapted to connect and disconnect said sets of instruments in pairs inrapid succession to and from the signal-conveying means, and tosimultaneously render operative and inoperative respectively thereceiving instruments of said pairs of sets, of a set of telegraphicinstruments at each end of the conducting means which carries thealternating current, the receivers of which sets of instruments are settoo high to be affected by said alternating current, and means inconnection with said sets of instruments last mentioned for addingincrements to the alternations of the alternating current, substantiallyas and for the purpose set forth.

9. In a multiplex telegraphic system, the

ductor, said device being such and arranged in such manner as to beoperated by the impulses passing in the first conductor, and a pluralityof devices consisting of electromagnets with rocking armatures adaptedto be controlled by the impulses in said conductors and to connect anddisconnect the sets of telegraphic instruments in pairs in rapidsuccession to and from the signal-conveying means.

10. In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be ca-s pable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, two line-wires each connected to one-half of the sets ofinstruments, means for repeating electrical impulses from one wire toanother in similar direction and proportionate strength, a separatesource of alternating electric current, means for conveying the currentfrom said source, and a plurality of devices consisting ofelectromagnets and rocking armatures controlled by said current adaptedto operate in pairs at rapidlysucceeding intervals of time to connectand disconnect the sets of instruments to and from their line-wires.

11. In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, two line-wires each connected to one-half of the sets ofinstruments, means for repeating impulses from one wire to another insimilar direction and proportionate strength, a separate source ofalternating electric current, means for conveying the current from saidsource, and a plurality of devices consisting of electromagnets androcking arinatures controlled by said current adapted to operate inpairs at rapidlysucceeding intervals of time to connect and disconnectthe sets of instruments to and from their line-wires, and tosimultaneously render operative and inoperative respectively thereceiving instruments of said pairs of sets.

12. In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, two line-wires each connected to one-half of the sets ofinstruments, means for repeating electrical impulses from one wire toanother in similar direction and proportionate strength, a separatesource of alternating electric current, a conductor for the current fromsaid source means for repeating the electrical impulses passing in saidconductor, a further conductor for said repeated impulses, and aplurality of devices half of which are adapted to be controlled by theimpulses in one conductor and half by the impulses in the otherconductor, said devices consisting of electromagnets with rockingarmatures adapted to connect and disconnect the sets of instruments inpairs to and from their line-wires.

13. In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means'for supplying continuous electric current to said sets ofinstruments, conveying means for the signals of said instruments, arocking armature between each of the sets of instruments aforesaid andsaid conveying means adapted to electrically connect and disconnect theset to and from the conveying means, two separate sources of continuouselectric current of opposite sign, a conductor, means adapted toalternately and at rapidly-succeeding intervals connect said sources tosaid conductor, and a plurality of electromagnets controlled by theimpulses in said conductor, adapted to operate the connecting anddisconnecting means aforesaid, in such manner that the sets ofinstruments are put in connection in pairs through the signal-conveyingmeans at rapidly-succeeding intervals.

1 In a multiplex telegraphic system, the combination of a plurality ofsets of telegraphic instruments each set such as to be capable ofcommunicating through one conductor with a similar set of instruments,means for supplying continuous electric current to said sets ofinstruments, conveying means for the signals of said instruments, arocking armature between each set of the sets of instruments aforesaidand said conveying means adapted to electrically connect and disconnectthe set to and from the conveying means, two separate sources ofcontinuous electric current of opposite sign, a conducting-wire, meansadapted to alternately and at rapidly-succeeding intervals connect saidsources to the conducting-wire, a second conducting-wire, means forrepeating the electrical impulses produced in said first conducting-wirein the second conducting-wire, and a plurality of electromagnetscontrolled by the impulses in said two conducting-wires

